(09-15) 18:56 PDT -- A running shoe apparently washed up on San Francisco's Ocean Beach on Sunday morning - which wouldn't be news except that inside was a human foot.

The grim discovery was made by the National Park Service beach patrol in a response to a call from a visitor to the section of the beach near Taraval Street. There was no sign of the rest of the body, and whatever happened probably happened some time ago, in some other place.

"What we have is a human foot, with some associated tissue, inside of a shoe," said Mark Powning, an investigator with the city's Office of the Chief Medical Examiner. "It probably was rolling around the seabed for awhile."